아빠는 공부쟁이

02:31 Competing chieftains quickly refined the new ships to be even more efficient. The lighter the boat, the more versatile it would be and the less investment of resources it would require— an essential advantage in a decentralized culture without large supplies of people. These ships still had no sails— sails were costly, and for now the rowed ships could meet their needs. chieftain 1. 지도자 2...